Plasma resonance in anisotropic layered high-Tc superconductors

The plasma resonance is described theoretically by the inductive coupling m odel for a large stacked Josephson-junction system such as the intrinsic Jo sephson-junction array in anisotropic high- T-c superconductors. Eigenmodes of the plasma oscillation are analytically described and a numerical examp le for the large stack case N=50 is given. The scaling length characteristi c of each mode is discussed. Numerical results for the plasma resonance for N= 50 in the presence of an external rf drive with wave number k are given . For k different from zero possible resonance modes among the eigen oscill ation modes are shown, and it is further demonstrated that for k=0 the reso nance takes place as a collection of N independent resonant Josephson junct ions. Some guidelines for possible experiments are shown. It is also shown that, very recent microwave experiments for the plasma resonance can be exp lained by this theory based on the inductive coupling, and collective longi tudinal plasma oscillations are discussed.